Cruising down the streets, while pumping out massive amounts of bass, boom cars are a fierce expression of urban individuality.

TIEFDRUCKGEBIET brings twelve of them together to form an orchestra and collectively create a physical listening experience.

Each of these cars only plays a single ultra-low sine tone, close to the limit of human hearing, tuned to make the car and the street resonate.

When all the individual tones merge, slowly pulsating sub-sonic rhythms evolve, creating what we like to describe as a low pressure area, or TIEFDRUCKGEBIET.

"Boom car – A vehicle containing a belligerent stereo system with subwoofers that render the trunk useless and broadcast low frequencies for hundreds of yards. The 'music' itself is designed to maximize bass, not musicality." – Urban Dictionary

How low can you go?

The boom car scene is about achieving maximum sound pressure by customising car stereos to the extreme. It's about playing extremely low frequencies on extremely high levels on extremely large speakers. It's about superlatives, fame, and competition.

TIEFDRUCKGEBIET puts these cars in a different context and presents them as instruments of an ensemble, turning their drivers into performers.

Did you know?

The sport of creating the highest possible sound pressure level inside a car is called "dB drag racing". No actual racing takes place, though. Some of the contestants even go as far as removing the motor from the vehicle to make room for the sound to resonate.

There's a storm coming.

TIEFDRUCKGEBIET explores the musical features of the frequency range below 60 Hz. This is real bass. This is where your ears stop working and you start to listen with your body.

In this range, a small cause will have large effects. A subtle change in tuning will make the difference between your chest and your stomach vibrating.

It's also the range where sound waves are so long, they can be tuned to make huge objects resonate – like cars, rooms, or even the streets.

Did you know?

Every object in the universe has its own resonance frequency, resulting from factors like its dimensions or material. For example, a standard tuning fork resonates at 440 Hz, while a car typically has a resonance frequency between 20 and 60 Hz.

Tuning up.

Every TIEFDRUCKGEBIET is a unique experience. That's because for each performance we co-operate with a local car tuning club.

The composition is based on the resonance frequencies of the cars, as well as those of the performance space: the street.

Before the concert, each car is measured acoustically to find its individual frequency of maximum bass response. That's the center of the car's playing range.

The dimensions of the performance space define the central frequency of the composition as a whole.

Getting down.

The concert itself is conducted live by the artists. Using their custom built software Weather Control, they induce ultra-low sine tones directly into the performing cars. Played through the cars' sub-woofers, and reflected from the walls of surrounding buildings, these frequencies build up a subliminal pressure that soaks your whole body in sub-bass.

Since all the cars are different, they play slightly different frequencies, too. When these detuned bass tones merge in the space between two cars, they influence each other, resulting in an acoustic phenomenon we call the WOW: a heavy pulsating of the air, ranging from slow modulations to fast-paced beats.

When all twelve cars play together, elaborate polyrhythmic structures emerge, creating a complex sub-sonic wave field that surrounds you completely. With each drop in frequency the field becomes more powerful, evoking a physical feeling of submergence.

The sonic effects differ immensely depending on the listener’s location. Get close to a car to feel its individual vibration or explore the whole space to fully experience the TIEFDRUCKGEBIET.

TIEFDRUCKGEBIET I

48h Neukölln Festival, Berlin (DE), 2011

TIEFDRUCKGEBIET was originally conceived for 48h Neukölln and won the First Art Prize of the festival. Eight cars moved around the 50 meters wide Schillerpromenade, pumping out sub-bass at 600 spectators. Only five sub-woofers survived the show.

TIEFDRUCKGEBIET I was supported by the excellent car audio supplier Schneller Hören.

TIEFDRUCKGEBIET II

Ars Electronica Festival, Linz (AT), 2012

The second coming of TIEFDRUCKGEBIET took place in the space below LENTOS Art Museum, Linz, when we came to Ars Electronica Festival 2012 to perform our full portfolio of sonic experiences. Instead of having the cars move around, this time the performance was focussed on bringing out the special sonic qualities of this highly symmetrical space.

TIEFDRUCKGEBIET II was performed by the incumbent European Champion of Car Audio, Martin Stangl, and his team Sound Masters.

What is the WOW?

When two slightly differently pitched tones are played back at the same time, a rhythmic modulation of volume will occur, ranging from complete silence to twice the volume of the original sound. This is what happens when a guitar is being tuned. We took this well-known effect to the sub-bass range and we call it the WOW. It’s the beating heart of several of our projects.

This is how it works: look at two slightly different sine tones as functions. You can simply add up their values at any given time and you will get a third function. This is the resulting sound wave.

Look closely at the graph – when the oscillation of tone A is at its positive peak (+1), while tone B is at its negative peak (-1), they add up to zero. Thus, no air is being moved: the tones cancel each other out, resulting in complete silence for a fraction of a second. Then they start to shift out of phase again, until two positive peaks are aligned, resulting in a doubled value (1 + 1 = 2, simple as that). This process repeats periodically, generating a steady beat. Throw in more detuned sines and the rhythm will become increasingly complex.

A lot more information on this can be found online, but don’t worry about the maths too much: you can enjoy TIEFDRUCKGEBIET even if you don’t understand exactly what is going on.